1. Field of the Invention
This invention relates to improvements in an operation control method of a multiple-phase weaving loom which weaves a plurality of fabrics located side by side, and more particularly to the multiple-phase weaving loom operation control method in which the loom is restarted after a mispicked weft yarn is completely removed.
2. Description of the Prior Art
A two-phase weaving loom has been proposed to simultaneously weave two fabrics and disclosed, for example, in Japanese Patent Publication No. 50-9904. This two-phase weaving loom uses a broad loom, in which warp yarns passed thereon are divided into two warp yarns arrays. A pair of weft picking nozzles are disposed between these warp yarn arrays and directed oppositely to project weft yarns fed from measuring and storage devices to the respective warp yarn arrays, thereby simultaneously weaving a plurality of fabrics.
With such a loom, when the loom stops owing to mispick caused in one of the warp yarn arrays, the weaving operation in the other warp yarn array having no abnormality is also unavoidably stopped, so that the total operational efficiency of the loom is low. In view of this, for the purpose of raising the loom operational efficiency and thereby to improve production efficiency, it has been required to shorten the loom stopping time for treating a mispicked weft yarn as much as possible by providing to the loom a function of automatically removing the mispicked weft yarn when a mispick occurs.
A loom operation control method for automatically removing a mispicked weft yarn has been already proposed and disclosed, for example, in Japanese Patent Provisional Publication No. 59-228047. This loom operation control method is as follows: When a mispick occurs during weft picking in which a weft yarn is projected from a weft picking nozzle, the loom is stops maintaining a condition where a mispicked weft yarn is being connected to the weft picking nozzle after beating-up the mispicked weft yarn. Subsequently, the mispicked weft yarn is exposed at the cloth fell and removed upon sucking carried out by a weft suction device. Thereafter, the loom is restarted.
Now, assuming that this loom operation control method is applied to the above-mentioned two-phase weaving loom so that the mispicked yarn removing means is provided to each warp yarn array, a mispicked weft yarn can automatically be removed when a mispick occurs in one of the two warp yarn arrays. However, in this case, a weft yarn normally picked simultaneously with the mispicked weft yarn remains unremoved in the other warp yarn array. As a result, in the first weft picking upon loom restart, a new weft yarn is added to the previously picked weft yarn picked in the other warp yarn array in which no mispick occurs. These two weft yarns are woven in the fabric thereby to form a section high in density or a heaving filling bar.
In addition, the mispicked weft yarn and/or the weft yarn normally picked simultaneously with the mispicked weft yarn unavoidably remains unremoved in the warp shed opening also in the case where the mispicked weft yarn has not been removed upon being entangled with the warp yarns and in the case where the mispicked and/or the normally picked weft yarn cannot be removed owing to any trouble of a weft traction device. Thus, in the first weft picking upon loom restart, a newly picked weft yarn is added to the remaining weft yarn similar to above-discussed operation, thereby causing weaving defects such as a heavy filling bar in the woven fabric.
Furthermore, there arises a situation that where a mispick will occur frequently or at every weft picking unless its cause is removed and that a yarn remains unremoved in the warp shed opening at every mispick. This corresponds, for example, to a case where the picked weft yarn is difficult to remove upon being caught by a reed blade to which foreign matter such as waste yarn is attached. In such a case, even weft picking is tried again, the operation of the mispicked weft yarn removing treatment and loom restart must be repeatedly carried out thereby to further prolong the loom stopping time. This will noticeably lower the operation efficiency of the loom.